1. Field of the Invention
The present invention relates to a CAD (Computer Aided Design) analysis result data processing apparatus, a CAD analysis result data processing method and a CAD analysis result data processing program for obtaining CAD (Computer Aided Design) processing data from analysis result data obtained from analytic simulation.
2. Description of the Related Art
There is a known analytic apparatus for dividing a model having a three-dimensional form into a plurality of elements and using the divided model (mesh model) to simulate and analyze a physical quantity such as a degree of distortion due to pressure. In the cases of displaying by three-dimensional CAD the model of analysis results (model after deformation) obtained by this analytic apparatus in the past, it often happened that the model processed by the analytic apparatus does not match with the model processed by CAD as to nodes and a basic coordinate to be handled, so that the coordinates of the nodes of the analysis results are manually rearranged to be processable by CAD and inputted to CAD.
FIG. 18 shows details of a flow of the process. Hereafter, as for the models to be analyzed, the model on CAD is referred to as a CAD model, and the model on the analytic apparatus is referred to as an analysis model. In addition, the above-mentioned analytic apparatus is comprised of an analytic solver and a post system. As shown in FIG. 18, first, the CAD model as a former model before the analysis is rendered as a mesh model and is analyzed by the analytic solver (S300) so that the results thereof are stored in a database D1. Next, the post system reads the analysis results of the database D1, and creates the analysis models (visualizing the analysis results) such as a deformation view and a contour view (S301). From this post system, coordinate value data of the nodes constituting the analysis models after the deformation is outputted to the database D2.
Next, arrangements of the nodes of the analysis models are manually checked by an operator (S302). Under normal circumstances, the nodes of the mesh model used for an analysis by the analytic solver are given arbitrary node numbers independently of the CAD model. There are many cases where, if such node data is taken as-is into the CAD, the CAD creates a curve by connecting the nodes in node input order (node number order) resulting in a CAD-drawn model different from what is intended. Therefore, it is necessary to check and correct the arrangement of the nodes before taking the data into the CAD. In S302, the operator imagines the form of the CAD-drawn model only from numerical data (coordinate values of the nodes) so as to rearrange the order of the nodes. The rearranged coordinate values are stored in a database D3.
The coordinate values after the deformation stored in the database D3 are inputted to the CAD. The CAD takes in the inputted coordinate values as points (nodes) for the curve so as to create the curve first. Subsequently, the operator creates the surface while manually determining the surface constituting a model boundary by using the created curve. All the surfaces thus created are merged and rendered solid by the CAD (S303).
The approach described above is a general approach conducted when taking the analysis result data into the CAD.
Apart from such an approach, there is another thinkable approach of using a surface-specific modeler for taking in point group data of the real thing measured with a three coordinate measuring machine or the like to surface and edit it. For instance, it is an idea that node coordinates in a deformed form obtained by the analytic solver are regarded as measured point group data so as to be taken into the surface-specific modeler and surfaced, and the surfaced data is taken into CAD.
In addition, apart from the surface-specific modeler, there exists dedicated software having a function of constructing the surface only from provided point group data.
However, in the case of the past approach shown in FIG. 18, its working efficiency is low since the operator has to imagine the form of the CAD-drawn model from the coordinate values of the nodes of the analysis model and manually rearrange the order of the nodes when inputting the data to the CAD. In addition, the manual work is apt to cause an error in the rearrangement so that it is not guaranteed to create an intended form surface by the CAD. Furthermore, while this approach is applicable to a model which is simple enough for the operator to estimate the form thereof from the coordinate values to an extent, it is not applicable to a model having a complicated form.
In addition, while graphics drawing/editing by the CAD only requires the model's outside form data, the approach using the surface-specific modeler has a problem that even the point group and surfaces inside the model which are unnecessary for the CAD are taken in, resulting in larger amounts of handled data and slower processing speed. Moreover, this causes a problem that, when taking the data into the CAD, it can no longer be automatically rendered solid due to the surface constructed inside the model. Furthermore, when surfacing, the surface-specific modeler constructs the surfaces by using all the points taken in and repeating complicated geometric calculation, and so there is no guarantee that the intended form will be obtained due to influence of a calculation error and so on. Moreover, its working efficiency is low since there are many cases where corrections such as movement and elimination of the nodes are necessary in the surfacing process.
In addition, the dedicated software having the function of constructing the surface only from the provided point group data has a problem that it is very expensive and its operation is difficult and requires a high-level technique.
To be more specific, according to the above-mentioned approach in the past, the analysis result data cannot be taken into the CAD fully automatically. In addition, there is a problem that, as all the node data of the analysis model is taken in and processed, output and processing of redundant data occurs.
The present invention has been conducted in consideration of the above circumstances, and an object thereof is to provide a CAD analysis result data processing apparatus, a CAD analysis result data processing method and a CAD analysis result data processing program capable of automatically obtaining only the information necessary for CAD processing from the analysis result data of analytic simulation with a simple mechanism and rendering the handled data lightweight.